1. Field of the Invention
The field of the invention relates generally to filters for storm water systems, specifically filter adaptable to fit over or work in conjunction with storm water inlet grates and the like. Such filters generally operate to keep sediment, debris and other unwanted material from entering a storm water drainage system.
2. Background Art
Storm water draining from construction sites or major roadways often contains suspended sediments. This may be especially true when rain encounters open soil sheet and runoff occurs. Runoff water can also carry with it debris and a variety of other pollutants such as, for example, metals, hydrocarbons, oils, trash, organic debris and the like. When water containing this unwanted material enters a storm water grate without filtering, it transfers all these pollutants into area waterways where they can disturb ecosystems and negatively affect water quality. This can result in major fines and non-compliance with federal regulations, such as the National Pollutant Discharge Elimination System (NPDES) and the Clean Water act.
Traditional storm water filtering systems require removal of the grate itself to install a filter, sometimes underneath the grate as a catch basin, and sometimes as an envelope that encompasses the entire grate. Removing a grate from a storm water entry requires significantly more labor, more equipment, less safety, less convenience and less ease of use as compared to installing an over grate filter of the invention.
In addition, the traditional storm water filtering systems are not designed to introduce treatments into the runoff. Their fasteners are often obtrusive, sometimes made of metal that when broken can damage vehicle tires and street sweeping equipment. Broken metal fasteners have the potential to become road hazards, damaging automobile tires and posing a slipping danger for pedestrians.
What is needed in the art, therefore, is an effective storm water filtering system that does not require removal of the storm water grate, is easy to install and to remove, allows for providing treatment of water for removal of metals, hydrocarbons and the like and is safe for vehicle tires and pedestrian traffic.